Writing instrument



FIG. 1 is a side elevation view illustrating a writing instrumentaccording to my new design;

FIG. 2 is a rear elevation thereof;

FIG. 3 is a side elevation thereof, from the opposite side from FIG. 1;

FIG. 4 is a front elevation;

FIG. 5 is a bottom end plan view; and,

FIG. 6 is a top end plan view.

An ornamental design for a writing instrument, as shown and described.